Steam-ejector



M. DELAPORTE.

STEAM EJECTOR.

APPLICATION FILED SEPT- 1. 1911.

1,328,270, Patented J an. 20, 1920.

/77. fiz/a/aorfa Hffo/"n @y MAURICE DELAPORTE, OF PARIS, FRANCE.

STEAM-EJ'ECTOR.

Specification of Letters Patent.

Patented Jan. 20, 1920.

Application filed September 7, 1917. Serial No. 190,119.

To all whom it may concern:

Be it known that I, MAURICE DELAPORTE,

a citizen of the French Republic, residing at No. 107 Ru Dareau, Paris, France, have invented certain new and useful Improvements in and Relating to Steam-Ejectors, of which the following is a specification.

This invention relates to an improved plant for extracting incondensable gases, such as air, from a steam condenser or any other receptacle in which a vacuum is produced, by means of the well-known arrangementof two or more steam ejectors working in series with one another. The practical use of plants of the kind just referred to has been delayed for some considerable time owing to the instability of the ej ectors work- 111g under the mentioned conditions.

One means for rendering the operation of the ejectors stable, by the addition of gas or vapor into the last ejector or ejectors of the series, forms the subject matter of my Patent No. 1306414, dated June 10th, 1919. This addition of gas or vapor has the object of insuring that the gaseous jet of the ejector to be rendered stable shall under all circumstances receive a suflicient volume to fill up the narrow section of this ejector.

The object of the present invention is to provide improved means for obtainingv the same result, that is to say, for insuring the stability of working of steam ejectors such as referred to. The improved means consists in introducing into the ejector or ejectors the stability of which is to be insured a small quantity of liquid, generally water, which is supplied thereto in a regular manner.

I. have ascertained from experiments which I carried out in this direction that in order to render an ejector stable it is suflicient to introduce therein a weight of liquid which is generally less than the weight of the steam delivered through the nozzle. The introduction of the liquid thus regulated alters but very little the extracting capacity of the ejector. The addition of liquid according to the present invention does not appreciably increase the volume of the gaseous mass of the jet delivered per unit of tim and if the liquid is cold it may even slightly decrease it. On the other hand, however, such addition substantially increases the average density of the gaseous mass in movement and consequently decreases the speed which the latter must attain in order to pass through the narrow section of the ejector, thereby causing the swelling up of the stream necessary to fill up the said narrow section of the ejector.

The addition of liquid, therefore, acts quite differently from the addition of gas in the prior arrangement hereinbefore re ferred to and although it leads to the same practical result the means provided accord ing to the present invention is sometimes to be preferred, as will be seen from the arrangements hereinafter more particularly described by way of example with reference to the accompanying drawings, in which Figures 1 and 2 illustrate diagrammatically two arrangements according to the invention.

Referring to the arrangement illustrated in Fig. 1; 1, 2 and 3 are three steam ejectors arranged in seriesWith one another and with two auxiliary jet condensers 4; and 5,'the gases to be extracted being drawn in through the inlet 6 and escaping into the atmosphere or into a medium of difierent pressure through the outlet 7. A receptacle 8 which is maintained full of Water is placed in communication with the ejectors 2 and 3 through pipes 9 and 10 which are provided with cocks or valves 12 and 11 respectively for regulating the amount of water it is desired to supply to the ejectors. The valves 11 and 12 may be provided with well-known of the ejectors is no longer to be feared.

One of the known means is shown in Fig. l and it controls the supply of water fed to the ejetOr 7. As shown in this figure, a pipe 26 places the interior of the condenser 5 in communication with a chamber, in which operates a piston 25*. A spring 27 tends to maintain the piston in lowered position and to keep the cook 11 opened, but as soon as the pressure in the condenser 5 is sufficient to raise the piston 25*, it will gradually cause said piston to close the valve 11.

The addition of Water lends itself to an automatic regulation which is very simple;

p pes. 9- and 10 respectively, and the midi Y tion of water will cease automatically when such addition is no longer required.

The height of the water column 9, for instance, is so selected that the atmospheric pressure ceases to be sufficient to raise the water up to ejector 2 when the pressure in the auxiliary condenser at becomes great enough to prevent the action of ejector 2 from becoming unstable.

In order to insure the stability of Working of the system it is sometimes quite sufficient to insurethe stability of the last ejector of the series of three steam ejectors. 4 and 5 are auxiliary condensers into which the injection water is admitted through the inlets 13 and 14: respectively, the water being withdrawn therefrom through the outlets 15 and 16 respectively by any suitable means such as by means of apump, a special steam ejector, or a pipe communicating with a receptacle having a higher vacuum.

The liquid to be introduced into one of the ejectors in order to insure its stability ofWorkillg may be supplied thereto through the same opening through which the gases are drawn in, or through an opening separate therefrom, such opening being arranged in the position shown in Fig. 1, or higher or lower than indicated, or at the neck of the ejector, or in its proximity.

The hquid may be injected through a nozzle of any desired shape and the injection may be effected in any desired direction, for instance in the direction of the current of steam.

- The liquid to be introduced into the ejector-may be obtained from one of the auxiliary condensers arranged in a preceding part of the series, more particularly when such aux liary condenser is of the surface type.

1g. 2 lllustrates an arrangement, in which jetcondenseris used in conjunction with two steam ejectors arranged in series with an auxiliary surface condenser. In this arrangement the addition of water into the last ejector is effected by sending into that ejector water obtained by the condensation of steam in the auxiliary condenser. The last ejector is so arranged that the water flows therein in a regular manner gradually as it is produced. By thus dispensing with any special device for withdrawing the water from the auxiliary condenser the installation is rendered'very simple.

Referring to Fig. 2, 17 is a jet condenser whlch may be of any suitable construction, and is supplied with cold water through a pipe 18 in which is inserted a small surface condenser 19 constituting the auxiliary condenser of an air extracting plant comprising two e ectors 20 and 21 arranged in series with each other. The first ejector 2O draws the gaseous mixture to be extracted directly from the jet condenser 17, the temperature of said gaseous mixture being generally previously reduced by its passage through a cooling device 22, which injects cold water into the suction pipe of the gases and reduces their volume in a known manner. The condenser 17 is illustrated with its usual accessory parts, viz., a water extracting pump 25, which is shown as being of the centrifugal type, and a valve 26 controlled by a floating member 27 for the admission of air from the atmosphere into the condenser, in order to decrease the vacuum in a known manner, when the water level accidentally rises. The steam of the jet in the ejector 20 and the steam contained in the mixture extracted from the main condenser 17 are condensed in the auxiliary condenser 19 and the water of condensation thus obtained is introduced into the last ejector 21 from which the steam escapes into the atmosphere together with the incondensable gases.

The steam is supplied to the two ejectors 20 and 21 through a pipe 23. An inspection cover 24 provided at the top of the pipe 18 permits of easily cleaning the tubes of the smallsurface condenser 19, although it is to be observed that these tubes are not subject to much incrustation since the temperature of the water does not increase to any appreciable extent while flowing through the tubes.

The method hereinbefore described for insuring the stability of working of steam ejectors working in series may advantageously be employed also in the case when a plurality of steam ejectors are arranged in series with a plurality of intermediate surface condensers. According to the dimensions recognized to-be the most favorable each ejector actually consumes its particular amount of steam, which is larger than the sum of the quantities of steam consumed by the preceding ejectors, and the successive ejectors have thus to extract quantities of water suitable for their capacity. I

The method of insuring the stability of working of steam ejectors arranged in series hereinbefore described may be used concurrently with other methods for insuring the stability of such ejectors.

a receptacle, comprising in combination-with a first and second steam ejector arranged in series With each other and an intermediate auxiliary condenser, means for introducing liquid to the mass of gas delivered to the second ejector, the inlet of said means being located at a point Where the gases extracted from the receptacle have already been subjected to a certain amount of compression, and means responsive to pressure variations in the auxiliary condenser for regulating the quantity of liquid admitted.

3. An apparatus for extracting gas from a receptacle comprising, in combination With a first and second steam ejector arranged in series With each other and an intermediate auxiliary condenser, means for introducing liquid into one of the ejectors at a. point where the gases extracted from the receptacle have previously been subjected to a certain amount of compression, and means responsive to pressure variations in the auxiliary condenser for regulating the amount of liquid admitted.

4. An apparatus for extracting gases from a receptacle comprising in combination With a first and second steam ejector arranged in series With each other and an intermediate auxiliary condenser, means responsive to pressure variations in said auxiliary condenser for introducing liquid into one of said ejectors at a point Where the gases extracted from the receptacle have already been subjected to a certain amount of compression.

5. An apparatus for extracting gases from a receptacle comprising in combination With venturi shaped first and second steam ejectors arranged in series with each other, and an intermediate auxiliary condenser means introducing liquid tothe second ejector of the series at apoint in advance of the throat thereof.

6. An apparatus for extracting gas from a receptacle in Which a vacuum is produced, comprising in combination With steam ejectors and an intermediate auxiliary con,- denser arranged in series With one another, means for supplying Water from the auxiliary condensere to the following e ector 01 the series, as set forth.

In testimony'whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

MAURICE DELAPORTE. 11. 3.

Witnesses:

CHARITE DAMAs, i J OSEPH GAMENIL. 

